Sewing machine with improved binder-feed arrangement

ABSTRACT

A double-needle sewing machine for the stitching of bound or piped slits in a fabric workpiece, e.g. a buttonhole or pocket slit in a piece of fabric adapted to form part of a coat or like outer garment, is provided with a feed arrangement for the binder strip designed to fold the latter into an inverted-T configuration. The latter arrangement is subdivided into a plurality of guide portions and a clamping device so that a portion proximal to the sewing machine may continue to feed the binder strips while a portion remote from the needles can be released to receive the binder strip for the next operating cycle.

United States Patent 1 Nicolay et al.

[451 July 24, 1973 p SEWING MACHINE WITH IMPROVED BINDER-FEEDARRANGEMENT [75] Inventors: Karl Nicolay, Bielefeld; Heniz Goldbeck,Brackwede/Westf, both of Germany [73] Assignee: Durkoppwerke GmbH,Bielefeld,

Germany 22 Filed: Apr. 17, 1972 21 Appl. No.: 244,780

[30] Foreign Application Priority Data May 11, 1971 Germany P 2123 160.7

[56] References Cited UNITED STATES PATENTS 6/1970 Miller 112/152 XLopez 112/65 Hester 112/152 ABSTRACT A double-needle sewing machine forthe stitching of bound or piped slits in a fabric workpiece, e.g. abuttonhole or pocket slit in a piece of fabric adapted to form part of acoat or like outer garment, is provided with a feed arrangement for thebinder strip designed to fold the latter into an inverted Tconfiguration. The latter arrangement is subdivided into a plurality ofguide portions and a clamping device so that a portion proximal to thesewing machine may continue to feed the binder strips while a portionremote from the needles can be released to receive the binder strip forthe next operating cycle.

10 Claims, 2 Drawing Figures SEWING MACHINE WITH IMPROVED BINDER-FEEDARRANGEMENT FIELD OF THE INVENTION BACKGROUND OF THE INVENTION In thepreparation of bound or piped openings in a fabric garment, it has beenthe practice heretofore to feed a binder strip, folded by appropriateguides, to a stitching site and to provide two rows of stitching whichare adapted to flank a slit cut into the fabric and forming the opening.In practice, the binder strip and the fabric workpiece are advancedtogether past the needles of the sewing machine, the binder strip beingapplied to the surface of the workpiece immediately ahead of thestitchforming means. The fabric workpiece or main piece of fabric maylie upon the stitching plate or table of the sewing machine while thebinder or piping material is fed to the surface of the workpiece fromabove, the folding and feed means being elevated to allow positioning ofthe binder strip and thereafter pressing against the binder strip andthe workpiece to hold it in place. The entire feed arrangement may besidplaced in accordance with the operating cycle of the operatingmachine to advance them past the needles.

In conventional apparatus of this type, the binder strips must beindividually positioned before sewing and the entire binder-feedarrangement must remain in the clamping or pressing position during theentire stitching operation. As a consequence, delays are encounteredbetween sewing cycles and it is not possible to prepare a new binderstrip or fabric workpiece without releasing the clamping and foldingarrangement for the prior binder strip and its workpiece. The durationof each cycle is, therefore, relatively long and the rate at whichsuccessive cycles can be carried out is limited not only by the sewingtime but also by the hiatus in operation of the feed arrangementnecessary for preparation of the material for the next sewing cycle.

OBJECTS OF THE INVENTION It is, therefore, the principal object of thepresent invention to provide an improved apparatus for sewing boundslit-like openings in a fabric workpiece. A more specific object of theinvention is the provision of an apparatus for binding or piping theedges of a slit-like opening, e.g. adapted to form a buttonhole, pocketor the like whereby the aforementioned disadvantages can be obviated.

Yet another object of the invention is to provide an apparatus for thesewing of bound pocket openings, buttonholes or the like in a fabricworkpiece, especially a piece of material adapted to form part of anouter garment such as a sack coat, by improving the feeding of thebinder strip and the folding thereof during the sewing operation.

Yet a further object of our invention is the provision of an improvedapparatus of the general class described, having increased output andoperating rate.

SUMMARY OF THE INVENTION These objects and others which will becomeapparent hereinafter, are attained, in accordance with the presentinvention, which provides a sewing machine for stitching the borders ofa slit-like opening, e.g. a buttonhole or pocket opening, with a binderstrip so as to reduce the dead time of the sewing machine and thefabric-fed apparatus by subdividing the binder-feed mechanism into aplurality of folding and clamping portions which may be operatedindependently so that the portion proximal to the sewing site may remaineffective in the feeding of one binder strip to the sewing needles whileanother portion of the feeding mechanism upstream therefrom can bereleased (without releasing the portion proximal to the needles) toaccommodate the next binder strip.

In other words, the dead time of the apparatus is reduced and theoperating rate or output increased by a system which, during the workingcycle of the sewing machine (i.e. during the sewing of a prior binderstrip to the workpiece) the feed arrangement or apparatus provides afree space for the positioning and arrangement of a fabric workpieceand/or the next binder strip, whereby the next cycle may commenceimmediately after the previous stitching cycle without any time loss forarrangement of the workpiece or binder strips.

According to an important feature of the invention, the workpiece-feedsystem includes an elongated member adapted to ride upon the worktableor stitching plate and shiftable parallel to the slit or opening to beformed, or previously formed, in the workpiece and transversely to theplane of a pair of needles adapted to stitch opposite sides of the slit.The elongated member displaces the workpiece toward the stitching siteand co-operates with a binder-folding orientation or clampingarrangement which is subdivided in the manner described while beingprovided with means for raising and lowering all or a portion of thelatter arrangement to receive and hold the fabric material.

In other words, the apparatus may comprise a sewing machine forming astitching site and a workpiecereceiving table or plate upstream from thestitching side while the elongated member bridges these two sites andmay have a length in the direction of fabric feed equal approximately tothe length of the workpiece. Co-operating therewith, there is a clampingdevice and a pair of folding rails each having a respective mechanismfor raising and lowering same and independently operable at least withinlimits to allow insertion of the binder strip in the rail upstream fromthe stitching site while a rail portion thereof downstream from thestitching site continues to guide the previous length of binder. The twoportions of the folding rail are thus provided in tandem, i.e. onebehind the other, at the upstream site of the sewing machine and areindependently elevatable and lowerable.

The device according to the invention thus enables the operator toposition a second workpiece and binder strip at the free space to theupstream side of the sewing machine while the previous workpiece andbinder strip are stitched together as they advanced by the feedmechanism past the stitching site. The dead time of the machine can thusbe practically reduced to zero as indicated earlier and the operatorremains active throughout the period of machine use.

DESCRIPTION OF THE DRAWING The above and other objects, features andadvantages of the present invention will become more readily apparentfrom the following description, reference being made to the accompanyingdrawing in which:

FIG. 1 is a somewhat diagrammatic vertical elevational view of theapparatus as seen looking toward the head of the sewing machine; and

FIG. 2 is a perspective view from above of a portion of this apparatus.

SPECIFIC DESCRIPTION The apparatus described and illustrated inconnection with FIG. 1 and 2 may be used for the production of stitchedslit-like openings in an outer-garment fabric such as a sackcoat. Tothis end, the sewing machine may be provided with a main cutting meansand second cutting means may be disposed below the table for producingshort incisions at each end of the main incision or slit to connect themain incision with each end of a stitch row paralleling the mainincision. In general, the stitch rows will be of the same length andwill start approximately simultaneously when the pocket opening is to beparallel to an edge or edge seam of the fabric piece. However, when thepocket opening is to be inclined to the edge or edge seam, one stitchrow will commence before the other stitch row, i.e. the stitch rows willbe of the same length but longitudinally offset from one another. Themain incision or slit between these stitch rows will generally be of alength shorter than the length of the stitch rows and will terminate inY-shaped slits, whose incisions connect each end of the main incision tothe respective end of a stitch row.

The stitch rows are formed by a pair of needles which may be providedwith control means for independent actuation so that, for example, oneneedle may be operated before the other to provide the longitudinaloffset described above. The main cutting means may be a blade disposedupon the sewing machine head and extending between the two stitch rowsto provide the main incision parallel to these rows. The other cuttingmeans may include a pair of angle cutters located on a common supportbelow the stitch plate or work table and adjustable in accordance withthe angle of inclination of the main slit and the stitch rows to theedge or each seam so that the length of these incisions of each Y isadjusted in accordance with the angle to provide a clean bond opening.Furthermore, each of the angle cutters may include blades pivotallymounted at the apex of a wedge-shaped pin upstanding from a support andprovided with actuating means for swinging these blades through anglesdetermining the length of the respective incisions as the support israised and lowered by a pneumatic cylinder. The control means mayinclude a further pneumatic cylinder connected with a slidable bar whoseposition determines the excursions of the blades and which operatesagainst a spring means via a pneumatic cylinder. The displacement of theslide bar may be determined by an adjustable abutment means adapted toset the angle of the main slit and stitch rows in accordance with theincision length and vice versa. A single programmer is provided for theincision length and slit angle. Such structure has been fully describedin the commonly assigned copending application Ser. No. 244,781 entitledSEWING APPA- RATUS FOR THE FORMATION OF EDGE-PIPING OPENINGS.

Reverting to FIGS. 1 and 2 of the present drawing, it will be apparentthat the apparatus comprises a support 1 and a table 2 which forms thestitch plate and a surface 20 across which the fabric workpiece isdisplaceable. A sewing machine 3 is mounted upon a support 1 and theplate 2 and comprises the usual post 3a with the operating mechanism forthe needles and any stitch-forming devices below the stitch plate, adrive wheel 3b, connected to a drive source for the apparatus such as anelectric motor by a clutch or other conventional coupling, an arm 3coverhanging the table and a head 3d disposed along the path of theworkpieces but thereabove. The head 3d is provided with a pair ofvertically reciprocable needle bars whose needles are shown in 3e and 3fand may be independently actuatable for the reasons described above. Inaddition, a cutting blade may be mounted at 3g to slit the workpiecebetween the stitch rows formed by the needles 3e and 3f. At the head 3dof the sewing machine, moreover, a guide 3h is provided. The guide 3hhas a bifurcated, downwardly open configuration to form a channel 3ithrough which the binder material is guided and designed to hold thebinder strip in an inverted-T orientation against the surface 321' of aguide member which is described in greater detail hereinafter.

The sewing machine may also comprise a conventional means for cuttingthe sewing thread automatically. It includes the previously mentionedblade for incising the workpiece to produce the main slit, the drivemotor which is not illustrated but is connected to the drive at 31) byan engageable and disengageable clutch and the handwheel 3b which servesfor positioning of the needle. If the motor is represented at M,therefore, it may be operated by a programmer P together with thevarious pneumatic and/or hydraulic and/or electrical devices for theworkpiece-feed mechanism. The clutch between the motor M and the sewingmachine 3 is represented at C The motor M is continuously driven duringthe operating period of the apparatus and the programmer P mayreversibly connect the motor to the V-belt pulley 4 via a further clutchC The pulley 4 is connected to a threaded spindle or lead screw fordriving the fabric feed apparatus here represented generally at 6.

The spindle 5 is'journaled at one end in a bearing plate 7 which may bemounted upon the sewing machine 3 while the other end of the spindle isreceived in a bearing plate 8 which is similarly supported on the table,e.g. via an adjustment device 8a for correct positioning of the heightof the assembly 5,6,7,8. The bearing plate 7 and 8 carry a pair of rails9 and 10 which extend horizontally parallel to one another inspacedapart relationship and are parallel to the spindle 5. The rails 9and 10 slidingly support a carriage ll which'is driven by the spindle 5and is connected to the fabricfed mechanism 6 via a linkage showngenerally at 12.

In FIG. I, the total horizontal excursion of the carriage 11 has beenforeshortened but is represented by the stroke X which must correspondat least to the stroke XI of the feed device 6 and, therefore, theapproximate length of the workpiece to be handled. The stroke X1 alsorepresents the displacement of the fabric-feed mechanism 6 during oneworking cycle.

Because of the large length of the spindle 5, we have found it to beadvantageous to provide additional support therefore in the form of arest 13. The spindle 5 is journaled in the center portion 13a of thisrest while the upper and lower portions 13b and 130 of this rest areslidably mounted upon the rails and 9 respectively. When the carriage 11is shifted to the right, the rest 13 is urged ahead of the carriage andis entrained on the return stroke by entrainment with the carriage 11via an arm 11a.

In the working direction (A) corresponding to the direction of advanceof the fabric, immediately ahead of the sewing machine 3, there isdisposed above the table 2 and parallel thereto, a shaft 14 which iscarried by an upright 16. The upright 16 comprises a post 16a (FIG. 2)in which the bar 16b is received, the shaft 14 being mounted on the bar16b via a clamp 16c. The clamp 160 has a bifurcated end forming twolobes 16d and 162 which can be drawn together by screws 16f to tightenthe clamp 160 against the bar 16b. The clamp 16c projects horizontallyfrom the vertical post 16 and carries a horizontal bar 15 which isreceived in the opposite bifurcated end of clamp 16s, the lobes of thisend being tightened by Allen screws 16f.

The clamp 16c can thus be raised and lowered along the post 16 to adjustthe height of the bar 14 and can be swung about the axis of post 16 toalign the workpiece-guide members with the needle site. The distance ofthe shaft 14 from the edge or edge seam of the fabric and from the edgeof the table 2 can be adjusted by loosening the screws 16f and shiftingthe bar 15 accordingly. The bar 15 is provided at its extremity remotefrom the clamp 160, with a bifurcated clamp 15a consisting of a pair oflobes 15b and 15c forming an opening 15d in which the shaft 14 isreceived. The lobes 15b and 150 are spanned by bolts 15e which tightenand loosen the clamp around the shaft 14.

The shaft 14 carries brackets 20, 21 and 22, each supporting arespective pheumatic cylinder 17, 18 or 19. For example, the bracket 20comprises a plate 20a to which the sleeve 20b is affixed and which canbe connected by the sleeve and its setscrew 200 with one end of theshaft 14 projecting forwardly beyond the clamp 15a. The plate 20a thuslies in a vertical plane. The plate 20a also carries a pair ofhorizontal blocks 20d and 20e in which the cylinder 17 and its pistonrod 17a is guided in the lower block 20e and a sleeve 20f projectingdownwardly therefrom. The lower block 20a is also provided with a stoppin 20g to control the stroke of the piston rod which is locked to aplate 17b by' screw 17c and thus operates against the force of a spring17d. v

The pneumatic cylinder 17 is disposed immediately ahead of the sewingmachine and is provided with an inverted-T profile folding guide 23 forthe binder strip. The guide 23 is, more particularly, pivoted at 23a toa shoe 23b at the lower end of the piston rod 17a. When a binder stripis fed to the guide so that the central portion of the strip underliesthe horizontal sole plate 231, the outer edges of the strip are bentaround the edges 231a and 231b and then up along the flanks of the .L-shank. The fabric is held in place by the guide foot 3h mentionedearlier.

Similarly, the intermediate cylinder 18 is carried by a bracket 21 whoseplate 210 has a sleeve 21b affixed to the shaft 14. The piston rod 18ais springbiased in the manner already described and carries the foldingguide 24 which likewise is of .L -configuration. The bracket 22 mostremote from the sewing machine has a pneumatic cylinder 19 whose pistonrod 19a operates a clamping bar 25 for tensioning the binder strip.

The shaft 14 also carries a bent bar 26 which supports a plate 27disposed below the clamping member 25 and extending only over part ofthe length of the guide 24. Pneumatic cylinder 17 lies generallyperpendicular to the plate or table 2 while the pneumatic cylinders 18and 19 are inclined at different angles to the table 2. The parts 24, 25and 27 together constitute a binder-feed arrangement for the binderstrip.

During a previous stitching cycle, the binder strip is placed upon theplate 27 and is clamped by a pneumatic cylinder 251 whose rod 252 rocksan actuator 253 to urge the shoe 254 against the binder strip. Below theplate 27, also during a previous stitching cycle, the main fabric piece,e.g. part ofa sack coat, is placed beneath the plate 27 and orientedwith respect to the opening slit by optical markings by the operator orautomatically. When, following the end of the earlier cycle, thefabric-feed arrangement 6 is elevated, and returned to the startingpoint, the fabric-feed shoes are lowered upon the workpiece under thecontrol of the programmer P, simultaneously the clamp member 25 islowered by its pneumatic cylinders 19 and the binder strip applied tothe top of the fabric-feed device.

The fabric-feed device 6 comprises two longitudinally extendingspaced-apart parallel rails or shoe members 60 and 61, each of which isconnected by three rods, representing the linkage 12, to a block 11bpivotal about the horizontal axis 11 1. The two shoes 60 and 61, whichhave the cross-sections of right triangles with corresponding verticesturned toward one another, define a gap a between them which receivesthe i-shaped rail 24 and folds the binder upwardly around the upstandingweb 24a of this guide. The approximately U-shaped binder strip isfurther folded by a pair of sheet-metal guide surfaces 62 and 63upwardly to the inverted T-configuration. These forming strips 62 and 63are provided with respective pneumatic cylinders 64 and 65 which operatethe bellcrank levers 66 and 67 fulcrumed on the rail 60 and 61 so thatthese sheet-metal members are urged toward the gap a parallel to oneanother because of the guide slot 68 in which pins 69 of the strips 62and 63 engage.

As the carriage 11 is shifted to the left, therefore, the main fabriclayer and the binder strip thereon are simultaneously moved to the left,the binder strip being thereupon drawn off the guide 24 and onto theguide 23 which is slightly bent upwardly at its upstream end 231. Whilethe binder strip continuesto be guided by member 23 and the sewingcommences,,cylinders 18 and 19 can be relieved to preparethe next binderstrip and fabric workpiece. The lengths of the'two folding rails 23 and24 are so dimensioned that rail 24 can be lifted as soon as the sewingmachine begins to stitch the new binder strip in place. Folding rail 23is only relieved when the full sewing operation has been completed. Theend 231 of the guide is thereby tilted upwardly to allow the nextworkpiece to be inserted.

While the main operating steps of the system have I been describedpreviously, it should be noted that at the end of one cycle, thefinished workpiece is drawn out from below the fabric-feed device 6which is lifted from the fabric under the control of the programmer andby means not further illustrated. The fabric-feed device is then shiftedto the right (FIGS. 1 and 2) in the elevated position to the region inwhich the next workpiece has already been positioned. The pneumaticcylinder 19 then applies the binder strip in the manner described andthe clamp 27 is thereby released and raised whereupon the cylinders 64and 65 are operated by the programmer to fold the strip about thepreviously lowered guide rail 24. The fabric is then shifted in thedirection of arrow A and the binder transferred to guide 23 aspreviously described. As soon as the transfer is made, member 24 iselevated and a fresh workpiece and binder strip prepared at the upstreamside of the table.

We claim:

1. An apparatus for the application of binder strip to a fabricworkpiece, comprising:

a sewing machine having a stitching site along a table and adapted tosew a binder strip onto a fabric workpiece at said site;

fabric-feed means shiftable along said table toward said site foradvancing a fabric workpiece in the direction of said site from anupstream location; and

binder-feed means along said table for positioning a binder strip onsaid fabric workpiece as said fabric workpiece is fed to said site, saidbinder-feed means including at least two folding members alignable insaid direction and independently operable to fold and guide the binderstrip fed to said site, and respective elevated means for each of saidmembers whereby the member proximal to said site may remain effectiveduring the stitching of the binder strip to the fabric workpiece whilethe member distal from said site is elevated to enable the preparationof another fabric workpiece and binder strip therebelow.

2. The apparatus defined in claim 1 wherein said binder-feed meansincludes a clamp upstream from said proximal member and co-operatingwith said distal member for retaining a binder strip during operation ofsaid distal member and thereafter delivering the retained binder stripto said distal member, said clamp being provided with a furtherelevating means operable independently of the elevating means of saidproximal and distal members.

3. The apparatus defined in claim 2 wherein said clamp and said distalmember are shifted by the respective elevating means at respectiveangles to said table and said proximal member is shifted by itselevating means perpendicularly to said table.

4. The apparatus defined in claim 3 wherein said proximal member has anend turned slightly upwardly and narrowing in the direction of saiddistal member for receiving a folded binder strip therefrom.

5. The apparatus defined in claim 4 wherein each of said members is ofinverted-T profile, each of said elevating means is a fluid-responsivecylinder and said apparatus further comprises:

an upright mounted on said table; a horizontal shaft mounted verticallyadjustably on said upright and overlying said table; and

respective brackets supporting each of said cylinders on said shaft withfreedom of angular adjustment about the axis thereof.

6. The apparztus defined in claim 5 wherein said fabric-feed meanscomprises a pair of rails extending in parallel spaced-apartrelationship in said direction and shiftable therealong from saidlocation to said site beneath said clamp and along said members, saidrails being spaced apart to receive said distal member and havingrespective folding plates shiftable toward each other for folding saidbinding strip about said distal member.

7. The apparatus defined in claim 6, further comprising a respectivepneumatic cylinder on each of said rails, operatively connected with therespective folding plate for displacing same parallel to itself.

8. The apparatus defined in claim 7, further comprising guide meansdisposed on said table adjacent said sewing machine and including a pairof support rails and a linkage connecting said carriage with saidspaced-apart rails of said fabric-feed means for displacing the latteralong said table and raising and lowering said fabric-feed means.

9. The apparatus defined in claim 8, further comprising a threadedspindle extending parallel to said support rails and driving saidcarriage.

10. The apparatus defined in claim 9 wherein said sewing machine is adouble-needle sewing machine provided with means for slitting saidfabric workpiece between rows of stitches formed by the needles.

1. An apparatus for the application of binder strip to a fabricworkpiece, comprising: a sewing machine having a stitching site along atable and adapted to sew a binder strip onto a fabric workpiece at saidsite; fabric-feed means shiftable along said table toward said site foradvancing a fabric workpiece in the direction of said site from anupstream location; and binder-feed means along said table forpositioning a binder strip on said fabric workpiece as said fabricworkpiece is fed to said site, said binder-feed means including at leasttwo folding members alignable in said direction and independentlyoperable to fold and guide the binder strip fed to said site, andrespective elevated means for each of said members whereby the memberproximal to said site may remain effective during the stitching of thebinder strip to the fabric workpiece while the member distal from saidsite is elevated to enable the preparation of another fabric workpieceand binder strip therebelow.
 2. The apparatus defined in claim 1 whereinsaid binder-feed means includes a clamp upstream from said proximalmember and co-operating with said distal member for retaining a binderstrip during operation of said distal member and thereafter deliveringthe retained binder strip to said distal member, said clamp beingprovided with a further elevating means operable independently of theelevating means of said proximal and distal members.
 3. The apparatusdefined in claim 2 wherein said clamp and said distal member are shiftedby the respective elevating means at respective angles to said table andsaid proximal member is shifted by its elevating means perpendicularlyto said table.
 4. The apparatus defined in claim 3 wherein said proximalmember has an end turned slightly upwardly and narrowing in thedirection of said distal member for receiving a folded binder striptherefrom.
 5. The apparatus defined in claim 4 wherein each of saidmembers is of inverted-T profile, each of said elevating means is afluid-responsive cylinder and said apparatus further comprises: anupright mounted on said table; a horizontal shaft mounted verticallyadjustably on said upright and overlying said table; and respectivebrackets supporting each of said cylinders on said shaft with freedom ofangular adjustment about the axis thereof.
 6. The apparztus defined inclaim 5 wherein said fabric-feed means comprises a pair of railsextending in parallel spaced-apart relationship in said direction andshiftable therealong from said location to said site beneath said clampand along said members, said rails being spaced apart to receive saiddistal member and having respective folding plates shiftable toward eachother for folding said binding strip about said distal member.
 7. Theapparatus defined in claim 6, further comprising a respective pneumaticcylinder on each of said rails, operatively connected with therespective folding plate for displacing same parallel to itself.
 8. Theapparatus defined in claim 7, further comprising guide means disposed onsaid table adjacent said sewing machine and including a pair of supportrails and a linkage connecting said carriage with said spaced-apartrails of said fabric-feed means for displacing the latter along saidtable and raising and lowering said fabric-feed means.
 9. The apparatusdefined in claim 8, further comprising a threaded spindle extendingparallel to said support rails and driving said carriage.
 10. Theapparatus defined in claim 9 wherein said sewing machine is adouble-needle sewing machine provided with means for slitting saidfabric workpiece between rows of stitches formed by the needles.